Nozzle spray test device



L. KAHLE ET AL NOZZLE SPRAY TEST DEVICE June 17, 1969 Sheet Filed June15, 1967 L Q, D llll llrll INVENTORS LLOYD L. KAHLE JOHN J SHANDOR BY 0MQMqM ATTORNEYS Sheet 2 of 3 INVENTORS LLOYD L. KAHLE JOl-l/V .1..Sh'AA/DOR a M m ATTORNEYS L. L. KAHLE ET AL NOZZLE SPRAY TEST DEVICEJune 17, 1969 Filed June 13, 1967 mm mm 8 m 8 @m I 33 m m v o O o mm 8mv ow n n #0 mm mm 5 on on 3 I L; L 55 3 i=5: n on o O U o 0 m mm R 3 gJune 17, 1969 L. KAHLE ET AL 3,449,948

NOZZLE SPRAY TEST DEVICE 4 Filed June 13, 1967 She et 3 as 57(ON 53)46(ON 45) 53 (BOTTOM) 56 (INTERMEDIATE) 45 ('TOP) 2 I ma.

JOHN J. SIM/V005 BY I ATTORNEYS United States Patent US. Cl. 73-119 18Claims ABSTRACT OF THE DISCLOSURE Nozzle spray test device fordetermining spray cone vertex angle of fuel injection nozzle and thelike.

Background of the invention In a jet engine or gas turbine for aircraftand the like it is a conventional practice to provide a multiplicity offuel spray nozzles (often arranged in circular series) to spray fuelinto an annular combustion chamber; and in order to achieve efficientoperation of the engine the nozzles must break up the fuel into smallparticles of predetermined size and must uniformly distribute the samein the form of spray cones of substantially equal vertex angles withoutexcessive overlap or underlap of the spray cones of successive nozzles.For this purpose, the nozzles must be manufactured within closetolerances with reference to assuring certain spray cone angles atspecified flow rates of fuel emerging from the discharge orifices of thenozzles and with reference to maintaining the nozzle and spray cone axescoaxial.

Summary of the invention The present invention is characterized in thata fuel injection nozzle to be tested is clamped in the test device andis connected to a fuel pressure source, the conical fuel spray issuingfrom the nozzle being directed into a chamber having aligned detectorsor probes which are adjustable radially inwardly or outwardly to be justcontacted or impinged by diametrically opposite slant height elements ofthe conical fuel spray.

The present invention is further characterized in that the distances ofthe ends of the probes from the spray cone axis are plotted in relationto vertex angles as lines on relatively movable visual graph means,preferably in the form of nested cylindrical charts or graphs, of whichthe respective lines will intersect at a point which denotes the vortexangle of the spray cone being measured. The charts are rotated by thesame mechanisms that drive the respective probes to move them radiallyinward or outward. Furthermore, if the aforesaid point of intersectionof the lines of the moving charts is above or below a fixed center lineextending parallel to the axis of said cylindrical charts, an indicationis given as to the number of degrees that the spray cone axis departsfrom the ideal nozzle axis in the plane of the slant height elementswhich impinge on the probe ends.

The present invention is still further characterized in that accuratemovements of the probes are achieved by eliminating backlash of gear andrack motion transmitting means; and in that means are provided foraccurate calibration of the device by the use of a master templet whichis mounted in place of the nozzle and which has diverging sides ofdesired vertex angle. With such tem- 3,449,948 Patented June 17, 1969plet in place the probes may be adjusted to contact the diverging sidesof the templet, and if the charts or graph means do not register thedesired vertex angle, couplings may be adjusted to bring the charts toproper indicating position without movement of the probes out of contactwith the sides of the templet.

Other objects and advantages of the present invention will becomeapparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention,then, comprises the features hereinafter fully described andparticularly pointed out in the claims, the following description andthe annexed drawings setting forth in detail a certain illustrativeembodiment of the invention, this being indicative, however, of but oneof the various ways in which the principle of the invention may beemployed.

Brief description of the drawing In said annexed drawing:

FIG. 1 is a front elevation view of a nozzl spray test device embodyingthe present invention;

FIG. 2 is a cross-section view taken substantially along the line 2-2,FIG. 1 illustrating the mechanisms for independently adjusting theprobes toward or away from the spray cone axis;

FIG. 3 is a cross-section view taken substantially along the line 33,FIG. 1 to illustrate the manner of clamping a typical fuel injectionnozzle for taking readings of the spray cone angle thereof;

FIG. 4 is a developed view of a stationary chart and two movable chartsin superimposed relation;

FIG. 5 is a diagram showing the movements of a probe as the vertex angleof the spray cone increases; and

FIG. 6 shows a templet by which the test device may be checked andcalibrated.

Description of the preferred embodiment Referring now more particularlyto the drawing, the test device as best shown in FIG. 1, comprises abase 1 on which is mounted a tubular spray chamber 2 having atransparent window 3 through which the fuel spray cone C emerging from anozzle N under test may be viewed during adjustment of the probes 4, 4.Each probe 4 has a ball-shaped end which facilitates longitudinalmovement of the probe until the ball surface is just tangent to a slantheight element of the fuel spray cone C. Centrally within the chamber 2is a light transmitting rod 5 as of clear acrylic plastic disposed toilluminate the spray cone C to facilitate accurate adjustment of theprobes 4, 4 as aforesaid, the rod -5 being capable, as Well known, oftransmitting light longitudinally therethrough from a light source, notshown, disposed adjacent the lower end thereof.

As shown in FIG. 3, a typical nozzle N may comprise a nozzle bodyassembly 6 having fuel lines 7 and 8 connected thereto and terminatingin a discharge orifice (not shown) within a surrounding shroud 9 whichis accurately fitted within a tapered wedge bushing 10 as of nylon. Thetop plate 11 of the test device also has mounted thereon a suitablenozzle clamp 12 and a nozzle locator 14, the clamp 12 herein being shownas a more or less conventional screw actuated clamping jaw 15. It is tobe understood that other forms of releasable clamping devices may beemployed to accurately locate and clamp the particular nozzles to betested.

Because the probes 4, 4 and associated adjusting mechanisms 20, are thesame except for being left-hand and right-hand as viewed in FIGS. 1 and2, the same reference numerals have been used to denote the same partsthereof.

As aforesaid, each probe 4 has a hemispherical end formed as by Weldinga ball 21 to the end thereof. The ends of the probes 4, 4 are coaxialand move along a line which is perpendicular to the axis of the idealspray cone. Each probe 4 is bent to provide a forwardly extendingportion 23 and an upwardly extending portion 24 which extends throughslots 25 in the top plate 11 and the body 26 of the mechanism 20. Theupper end of each probe 4 extends through a gear rack 27 and is clampedtherein by a setscrew 27, said gear rack 27 having its end portionslongitudinally slidable in the nylon or like guide bushings 28, 28disposed in the ends of said body 26.

Meshing with said gear rack 27 is a drive pinion 29, the shaft 30 ofwhich extends through an eccentric bushing 31. By rotating the bushing31 the gear teeth of the pinion 29 and rack 27 may be wedged together toeliminate any backlash or looseness, and thus greater accuracy ofadjustment of the probe 4 is achieved. The shaft 30 of each gear 29 isconnected to an adjustable coupling 32 such as for example a coupling ofthe type disclosed in the patent to Raskhodoff, No. 3,024,629. Eachcoupling 32 has secured thereto an adjusting shaft 34 which is adaptedto be turned in opposite directions as by the knob 35 at the endthereof, said shaft 34 being supported for rotation as in nylon or likebushings 36, 36 in a body 37 fixed on the top plate 11. Each adjustingshaft 34 has keyed thereon a bevel gear 38 which meshes with a bevelgear 39.

Extending between the bodies 37, 37 and fixed thereto as by the pins 40is an outer tube member 41 as of stainless steel which has a window 42provided with indicia ranging from 70 to 120 to denote the vertex anglesof fuel spray cones being measured and with the numerals 0 to 5 aboveand below the 0 point to denote the angular misalignment or skewing ofthe spray cone under test from the true centerline of the perfect spraycone. Affixed to the outer cylinder 41 as by the pins 43, is atransparent cylinder 45 which has uniformly spaced vertical lines 46scribed on its inside diameter which are the vertex angle degrees forthe 70 to 120 numbers appearing longitudinally along the upper edge ofthe window 42. This transparent cylinder also has lines 47 scribedlongitudinally along its inside diameter which diverge slightly towardthe right to correspond with the numbers 0 to 5 appearing vertically atthe right-hand edge of the outer cylinder window 42.

In the case of the left-hand mechanism 20, the shaft 50 of the bevelgear 39, through the bellows spring 51 and the drive pins 52 rotates theinnermost or first cylindrical chart or graph 53, whereas in the case ofthe righthand mechanism 20, the rotation of the bevel gear shaft 50through the bellows spring 51 and the drive pin 54, rotates theintermediate or second cylindrical and transparent chart 56.

It is to be understood that the spray cone vertex angle range of 70 to120 has been selected because it has been found that fuel nozzles allhave spray cone vertex angles in this range.

Reference will now be made to the lines which are scribed on therespective first and second rotatable cylinders 53 and 56 and the thirdstationary cylinder 45 as shown in FIG. 4 which show said cylinder indeveloped fiat form and superimposed on one another.

In FIG. 4 the curved line 57 is scribed on the outside diameter of thefirst cylinder 53 which is rotated by the left knob 35 of the testdevice; the curved line 58 is scribed on the inside diameter of thesecond cylinder 56 which is rotated by the right-hand knob 35 of thetest device; and the vertical lines 46; and the diverging lengthwiseextending lines 47 are scribed on the inner surface of the stationarythird cylinder 45, the vertical lines 46 corresponding to the spray coneapex angle markings 70 to along the upper edge of the window 42 of theouter metal tube 41.

The lines 57 and 58 are plotted as best shown in FIG. 5 by plotting theball 21 center locations along the line 59 which is a constant distancey from the apex of the spray cone. The ball center location is thedistance x plus x from a zero reference line or spray cone axis 60,since the range for the present device is from 70 to 120 apex angle 0.

The following formulae may be used in plotting the distance x plus or atany angle 0/2 from 35 to 60:

(y' and R are constants) It can thus be seen that when the first andsecond cylinders 53 and 56 are rotated equal amounts in oppositedirections from their zero reference points, the lines 57 and 58 willcross at the center "0 horizontal line 47 at a vertical 46 to denotevertex or apex angle 0 of the spray cone C under test. In the exampleshown in FIG. 4, the lines 57 and 58 cross at about 101 vertex angle andthe balls 21 of the probes 4, 4 are equally spaced from the zeroreference axis 60 of FIG. 5.

However, if the spray cone axis is tilted, the end of one probe 4 willbe closer to the true axis 60 than the end of the other probe 4, andthis will be indicated in FIG. 4 (and also FIG. 1) by the intersectionof the lines 57 and 58 above or below the center 0 line 47. If theintersection of lines 57 and 58 is above the center line 47, theright-hand probe 4 has not moved in as far as the left-hand probe 4 andvice versa if the intersection of lines 57 and 58 is below the centerline 47, the lefthand probe 4 has not moved in as far as the right-handprobe 4. However, in either case, the point of intersection of lines 57and 58 indicates the total apex .angle 0.

The diverging lines 47 on the stationary third cylinder 45 are a plot ofthe increasing rate of ball movement along line 59 of FIG. 5 per degreeincrease of the angle 0/2 from 35 to 60. This is also evident from theincreasing slopes of the curves 57 and 58 in FIG. 4.

While in the preferred embodiment of this invention the probes 4, 4 arevisually positioned by rotating the left and right knobs 35, 35 to justtouch the spray cone slant height elements, it is to be understood thatother forms of probes may be employed which will energize a visible oraudible signal when the probes just touch the outer surface of the spraycone C. As one example, the probes may comprise pneumatic transducers tomeasure the force of fluid impingement on the probes, thus to eliminatehuman visual observance of probe contact with the spray cone C, and, inturn, the transducers may control motors to stop the probe advance orset off a visual or audible signal, due to contact of the outer surfaceof fuel spray with the probe.

It is to be noted that the lines 57 and 58 scribed on respective first.and second cylinders 53 and 56 are scribed on the outer and innersurfaces thereof thus to eliminate error due to parallax. Likewise, thesecond cylinder 56 is made quite thin so that the internal markings onthe stationary third cylinder 45 will be relatively close to the lines57 and 58 thus to minimize reading error due to parallax.

In setting up the equipment to test a series of spray nozzles which areto have a specified spray cone angle within certain limits such as plusor minus 2, a templet 61 (FIG. 6) is placed between the probes 4, 4 sothat the vertex location corresponds to that of the ideal nozzle spraycone. With the templet 61 thus located, the left and right-hand knobs 35are turned to bring the ends of the probes 4, 4 into contact with therespective diverging sides 62 of the templet 61. If the templet 61 has,say, a

90 vertex angle, then the lines 57 and 58 should intersect each otherand the center 0 line 47 at the 90 angle designation. If the lines 57and 58 do not thus cross at 90, then either or both couplings 32 areadjusted to turn the knob shaft or shafts 34 with respect to the gearshaft 30 in a direcion such that the line 57 and/or line 58 do cross thecenter line 47 at the 90 indication.

With the equipment thus calibrated, nozzles N to be tested may then besuccessively clamped in the test device and connected to a fuel pressuresource, whereupon the left .and rightknobs 35 may be manipulated to movethe probes 4, 4 into contact with or into close proximity to the surfaceof the spray cone C. When that has been done, the operator will readcharts 53, 56, and 45 to determine whether or not the spray cone angle 0is within the specified tolerance limits and whether or not the spraycone axis is askew with respect to the desired true axis 60. The maximumamount of skew angle is usually contained in nozzle specificationsbecause excessive variation in that angle in the plane herein shown mayresult in excessive overlap or excessive spacing between the edges ofthe sprays C when installed in a jet engine. If it be desired to readspray cone vertex .angles 0 and skew angles in diiferent planes,additional probes 4, 4 may be provided or the nozzle N under test may berotated about the spray cone axis. However, single readings ascontemplated with the present equipment will usually suffice.

Other modes of applying the principle of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims, or the equivalent ofsuch, be employed.

We, therefore, particularly point out and distinctly claim as ourinvention:

1. A test device for spray nozzles and the like comprising nozzlemounting means; aligned probe means movable toward and away from eachother into close proximity with opposed slant height elements of a spraycone emerging from a nozzle held in said mounting means; drive means forthus moving said probes; and visual indicating means actuated bymovement of said probes from which the vertex angle of the spray coneunder test may be read. 7

2. The device of claim 1 wherein said indicating means have indiciathereon converting distances of said probe means from a reference coneaxis to a vertex angle readmg.

3. The device of claim 1 wherein said indicating means comprisessuperimposed movable graphs actuated by movement of the respective probemeans, and a stationary graph; said graphs having indicia thereonconverting distances of said probe means from a reference cone axis to avertex angle reading.

4. The device of claim 3 wherein said indicia comprise oppositely slopedlines on the respective movable graphs and vertex angle degree lines onsaid stationary graph, said oppositely sloped lines intersecting eachother at a line of said stationary chart corresponding to the vertexangle of the spray cone of the nozzle under test.

5. The device of claim 4 wherein said stationary graph has a center linetransverse to said degree lines thereon, said oppositely sloped linesintersecting along said center line if the angles on opposite sides of areference cone axis are equal and intersectingto one side or the otherof said center line if the angles on opposite sides of a reference coneaxis are unequal.

6. The device of claim 3 wherein said graphs comprise nested cylindersof which at least the outer two are transparent to render visible theindicia of all three graphs.

7. The device of claim 3 wherein the indicia of each movable graphcomprises a line which represents the distances of the associated probemeans from a reference cone axis at various angles of the adjacent slantheight element from such reference cone axis.

8. The device of claim 1 wherein said drive means has couplings foradjustment of said indicating means with respect to the respective probemeans whereby said probe means and said indicating means may beaccurately preset in conjunction with a templet having an accuratevertex angle whose reference axis is perpendicular to the path ofmovement of said probe means.

9. A test device for spray nozzles and the like comprising a hollow basemember having an aperture through the top thereof and having a viewingwindow through which a spray cone of a nozzle positioned in the aperturemay be observed; aligned probe means within said base movable toward andaway from each other along a line which is perpendicular to a referencecone axis passing through the center of said aperture; drive means forthe respective probes operable to move the ends of said probes intoclose proximity with opposed slant height elements of a spray coneemerging from a nozzle inserted into said aperture; and visual graphmeans actuated by movement of the respective probes indicating theposition of each probe end in terms of the angle between said referencecone axis and the adjacent slant height element.

10. The device of claim 9 wherein said graph means comprisessuperimposed movable graphs thus actuated by the respective probes, anda stationary reference graph.

11. The device of claim 10 wherein said movable graphs have oppositelysloping lines thereon that intersect each other at a reference line onsaid stationary graph denoting the vertex angle of the spray cone of thenozzle being tested.

12. The device of claim 10 wherein said graphs comprise nestedcylinders, of which those actuated by the respective probes, are rotatedabout their coinciding axes in response to movement of said probes.

13. The device of claim 12 wherein the rotatable cylinders have lines ofopposite slope thereon that intersect each other at a reference line onsaid stationary cylinder denoting the vertex angle of the spray cone ofthe nozzle being tested.

14. Visual graph means for measuring the vertex angle of a liquid spraycone comprising two probes, means mounting said probes for radialmovement into close proximity with angularly spaced slant heightelements of a liquid spray cone whose vertex angle is to be measured,three cylinders telescoped within one another, means mounting two ofsaid cylinders for rotation in opposite directions in response to suchradial movement of said respective probes while said third cylinder isheld stationary; said two rotatable cylinders having lines of oppositeslope thereon which intersect each other, and said stationary cylinderhaving reference lines thereon denoting the vertex angle of the liquidspray cone being measured where said lines of opposite slope intersect.

15. The graph means of claim 14 'wherein at least the intermediate andouter cylinders are transparent to render visible said lines of oppositeslope on said rotatable cylinders and said reference lines on saidstationary cylinder.

16. The graph means of claim 14 wherein said rotatable cylinders areadjacent each other and said lines of opposite slope are disposed on theouter and inner surfaces of said adjacent rotatable cylinders thus tominimize parallax in the observance of the point of intersection of saidlines.

17. The graph means of claim 14 wherein said stationary cylinder has anaxially extending center line thereon along which said lines of oppositeslope intersect if a reference cone axis 'bisects the measured liquidspray cone.

18. The graph means of claim 17 wherein said stationary cylinder hasadditional lines on opposite sides of said center line which denote themagnitude of inequality of measured angles from said reference cone axiswhen said lines of opposite slope intersect each other on one side orthe other of said center line.

References Cited 'UNITED STATES PATENTS RICHARD C. QUEISSER, PrimaryExaminer.

JERRY W. MYRACLE, Assistant Examiner.

US. Cl. X.R. 34649, 138

